docs: def delete_preferences(queryset):
      """
      Delete preferences objects if they are not present in registry. Return a list of deleted objects
      """
      deleted = []
  
      # Iterate through preferences. If an error is raised when accessing preference object, just delete it
      for p in queryset:
          try:
              pref = p.registry.get(section=p.section, name=p.name, fallback=False)
          except NotFoundInRegistry:
              p.delete()
              deleted.append(p)
  
      return deleted